Ok, so I've had this noise, a clunking that sounded like something was loose and clanking against something. Since the brains that put my engine in (before I bought it) only put one bolt per side to hold the exhaust up I figured it was that. So after pulling the exhaust manifolds and tapping new holes it's all back together and tight. By the way it's a 454 TBI w/turbo 400.

Yet the noise is still there. We think we've narrowed it down to the torque converter or the cat. It doesn't do it all the time, sometimes under load others when it's just idling. It runs fine otherwise(I still have to get the map sensor) but it's driving me nuts!!!!!!!!!!

I just read someone elses post on his converter going out. Is this possible? The torque converter is just a guess.

HELP!!!!!!!!

Not exactly clear about the clanking sound. I have never heard of a converter making sounds unless it was coming apart...I cant see that happening.

The first thing I would check is your motor and trans mounts and see if the motor and trans is moving. have someone stand on the brakes, open the hood, put it in gear and stomp on the gas. check the engine moving.

Can you recreate the noise while watching it? good luck Randy.

I don't know if is the same noise or not but earlier this summer, I had a clunking noise on my 2000, I swore it was my exhaust rattling on some thing but found out it was one of my cats. The honeycomb thing inside broke into 2 pieces and was clunking around in there. It also plugged off the exit and got so hot inside that it melted the core some and just made matters worse.

cheak your torq converter boults dude thar proboly lose

erik

The bolts are tight. That was easy. I'm going to pull the cat tomorrow. I figure it can't hurt. I'll let you know!

Ok I pulled the cat. That didn't sound right. Anyway, it's much better. Revs smoother and my Flowmaster can sing now! But....

It's still makes the noise. Not as bad but it's still there. The search continues!!!!!!!!!

How bout U-joints?

My '86 had some heat shields on the exhaust that ended up rattling, I just had them cut off.

Ujoints are ok. I took the heat shields off. What is the point of the drivers side shield?

Still looking. Thanks for everyone's help.

make shur none of the peases of the cat are in your muff . the cats brake apart and send stuff down streem

How in the hell am I suppose to do that?